The key privacy interest that commercial facial recognition affects is, of course, identification of an individual through facial features alone. Without facial recognition technology, it is very difficult for a stranger to easily and quickly identify an individual on this basis. Individuals in public currently expect that most businesses and passersby cannot recognize their faces, fewer still can connect a name to their faces, and few – if any – can associate their faces with internet behavior, travel patterns, or other personal information. Facial recognition technology fundamentally changes this dynamic, enabling any marketer or random stranger to collect – openly or in secret – and share the identities and associated personal information of any individual in public.

Deployed widely enough, a network of facial recognition cameras can track millions of individuals as they move from place to place. Unlike other tracking methods, such as GPS or RFID, facial recognition does not require the tracked individual to carry any special device or tag, reducing consumers’ ability to thwart unwanted tracking. Once built, databases assembled with facial recognition for commercial use can be accessed or re-purposed for law enforcement surveillance...